lead in forcing cone

msn_jrd · November 29, 2008, 11:40:42 AM

whats the best way yall have found to help with the lead build up in the forcing cone I'm shooting 38 in a 357 so am i just going to have to deal with it oh and if you know of any fast ways to clean it out id like to know that too

Sgt. Jake · November 29, 2008, 12:36:49 PM

What kind of loads are you using in it ? One of the things that can cause leading in the forcing cone area is bullets of the wrong dia., have you slugged the bore,to determine dia. then there is the dia.of the cylinder throats themselfs. One of the other things to mind,is light loads with hard cast bullets. When light powder charges are combinded with commericial hard cast lead,the forcing cones tend to show leading like you describe. One of the ways you can clean it up is with the use of a Lewis lead removal rod,available at Brownells,but the best way to deal with is figure out whats causing it,and take the nessary steps to resolve it.JMO Adios Sgt. Jake

msn_jrd · November 29, 2008, 01:06:49 PM

ok ill check in to it and see what i come up with
thanks

Sagebrush Burns · November 29, 2008, 09:33:35 PM

Another potential issue is the use of bevel base bullets. When using relatively lower pressure loads bevel base bullets, undersize bullets, too hard bullets can all contribute to leading in the forcing cone area. Most likely issues with commercial cast bullets these days is too hard and bevel base. For clean-up the M-Pro 7 line of products (available from Brownell's and Midway) work real well.

Sgt. Jake · November 30, 2008, 10:51:17 AM

Sagebrush Thanks,should have mentioned that. I dont own any bevel base molds and wont buy bevel base bullets eithier. Adios Sgt. Jake

Will Blastem · November 30, 2008, 06:54:28 PM

Just curious...Is a bevel base bullet one which has a concave bottom or is it one which is flat but the sides are beveled?
If it's the latter, how does that cause leading?...and what is the purpose of the bevel other than perhaps to aid in hte loading process to prevent "shaving" the bullet when seating?

Coffinmaker · November 30, 2008, 07:00:12 PM

Bevel base is when the bottom of the bullet is flat, and the last 32nd or so has a slight bevel. The principle reason is to aid in loading. Helps prevent shaving.
The cause of the leading is the gasses sloughing off a tiny bit of lead as the bullet enters the bore and depositing the lead at the forcing cone.
The other cause can be too steep an angle of the forcing cone. Many guns have a very steep forcing cone or in some cases, none at all. Look at that as well.

Coffinmaker

Will Blastem · December 01, 2008, 06:07:57 PM

Quote from: Coffinmaker on November 30, 2008, 07:00:12 PM
Bevel base is when the bottom of the bullet is flat, and the last 32nd or so has a slight bevel. The principle reason is to aid in loading. Helps prevent shaving.
The cause of the leading is the gasses sloughing off a tiny bit of lead as the bullet enters the bore and depositing the lead at the forcing cone.
The other cause can be too steep an angle of the forcing cone. Many guns have a very steep forcing cone or in some cases, none at all. Look at that as well.

Coffinmaker

Thanks

w.b. masterson · December 19, 2008, 06:02:11 PM

Also, if the leading gets too severe, you might try one of those deplating kits. I believe RCBS makes them. They reverse plate the lead onto a rod going down the barrel. They will remove both lead and copper fouling from barrels. I've had almost a full bullet of lead to accumulate on the rod after a long match. (Yes, I use bevel based bullets to help with progressive reloading). I never had this problem with my own bullets, but bevel-based bullets allow the gas to leak by and cut the base of the bullets. No cure for that with progressives and still keep up the speed loading. I've used the Lewis tool, but sometimes, it just won't cut the lead out.

August · December 19, 2008, 10:44:53 PM

Hard bullets are often the cause of leading problems. Cylinders with an undersized throat will cause leading in the forcing cone also. Roogers are noted for this issue, but other gunz are similarly afflicted. Indexing issues will almost certainly result in leading of the forcing cone.

How much "splash" are you getting on the cylinder face??? This is a pretty reliable indicator of indexing problems.

I have used a Lewis Lead remover on forcing cones with success. Run the rod down from the muzzle, attach the screen and plug, twist to your hearts content while pulling against the forcing cone. Works best of anything I've tried. Also, you can chuck up a bore brush and run it just into the cone (carefully). Again, you'll assemble the brush in the same way as I've described the Lewis procedure.

At the very least, your pistol would benefit from having a gunsmith open up the forcing cones to the 11 degree configuration that seems to eliminate all timing and indexing issues (except severe ones). You should, however, also mic the cylinder throats and bore to be sure the bullets are not getting distorted before they even get to the forcing cone.

After pooping around with revolvers for many years, I've decided that gunsmiths are invaluable and underpaid.

Oklahoma Joe · December 27, 2008, 05:59:54 PM

I've found that JB Bore Compound scrubbed with a bristle brush is a quick and sure-fire remover of all metals in bores and forcing cones... just be sure to not let any of it get into any crevices and crannies as it is an abrasive. It made an old S&W 629 lead pipe squeaky clean when I pulled a patch through it. Squeaky!